Don’t Blink (Does Logic Betray Us?)

In my last little rant about 212:The Extra Degree, I described how the main thing that offended me about the whole movement was the ill-informed metaphor they use. I hate a bad metaphor based on bad reasoning. That got me thinking of the times I’ve been told that "logic betrays us" by which the person saying it usually means that "common sense" often provides superior information to logic. Let me be the first genius to tell you that a little bit of common sense should tell you that isn’t true. Saying logic betrays us is like saying hammers betray us. Hammers betray us when we try to use them to drive machine screws into sheet metal, but for sinking a nail into a piece of wood, a framing hammer is a damn reliable tool. Logic too is an utterly dependable tool: you can depend on it to bring you to solid conclusions if it is used well and based on good assumptions. You can, on the other hand, depend on it to bring you to the most absurd conclusions if used incorrectly or if you start from faulty assumptions. In this age of American unreason (see Susan Jacoby, The Age of American Unreason or Chris Mooney, The Republican War on Science) I guess it’s necessary to point that out.

Malcolm Gladwell made a big splash with Blink: The Power of Thinking Without Thinking, a book that argues that often our gut reactions can get us to the same result as considered reflection, but much quicker and with surprising reliability. I don’t refute that and it’s often true, though my favorite book that makes that point is Gavin de Becker’s The Gift of Fear (a great read). In any case, under some circumstances where we have a need to process lots of information quickly (fighting a structure fire, escaping a rapist), our instinct is often a better guide than reason because we may not have time to apply our reason before we get killed, but subconscious processing in our minds often finds a viable solution rapidly. Damn useful. But I see the idea extended in support of unreason and the belief that our gut reactions trump considered reflection (and I don’t blame Gladwell for that). If there’s time to consider and reflect and, more importantly, to test, that’s better. Always.

Logic by its very nature can be neither loyal nor disloyal, and therefore can never betray. Whenever you hear that we cannot trust reason, be prepared because you are about to be fed some bullshit, perhaps innocuous, perhaps dangerous. Reason cannot always provide a satisfactory answer to our questions, our needs and our hopes. It’s not always the solution, but it never betrays us. We cannot always trust to reason, but we can always trust reason.

I remember in particular two cases in particular from my late teens where I was told that logic is a poor guide and I was told this in contexts where you would least expect it: in the preface to a book of logic puzzles and in a philosophy class in college.

The fake syllogism.

I was in a philosophy class taught by a great and inspiring teacher, but not a man whose logical faculties were not highly developed. He was making the argument that the Nazis used logic to show that because Jews were bad, Nazis were good. The syllogism he gave was this one:

Proposition 1: All Jews are bad.
Proposition 2: We are not Jews.
Conclusion: Therefore we are good.

I don’t refute that this is part of appeal of anti-semitism for the Nazis and others, but it has nothing to do with logic. A fundamental aspect of a syllogism is that any terms can be replaced and it still makes sense as long as the propositions are equivalent. Again, logic is neither loyal or disloyal, merely a tool. So that syllogism is the same as this one:

Proposition 1: All elephants have eyes.
Proposition 2: We are not elephants.
Conclusion: Therefore we do not have eyes.

In any undergraduate class, 10% are paying close attention to what the teacher is saying and really understanding it, 10% are utterly confused and lost, and the other 80% are having sexual fantasies. That’s been proven. Miraculously, on the day in question, yours truly was in the 10% who were paying attention. So I pointed out the problem with the syllogism and was told by some very smart people, including the professor and someone who is now a top cardiologist, that I wasn’t getting it. "It’s a simple syllogism" I was told. No, it was a faulty syllogism, and potent as such, but it was unreason that allowed such lies to be perpetrated, not reason. Reason did not betray the Jews, unreason betrayed them.

Of steam and ice.

James Fixx, who wrote The Complete Book Of Running, a major bestseller in 1970s that helped popularize running, also wrote the lesser-known Games for the Super Intelligent. I owned it, but my pride is not such that I bought it. It was a gift. A joke I think. In any case, that book or its sequel asserted in the preface that fun as the logic games within may be, sometimes logic betrays us and is a poor guide. If I remember right, he pointed out that a cocktail had about 350 calories (I’m making up the number — it may have been, but the principle and the error will be the same). Now, he pointed out that it takes 80 calories per gram to melt ice. So, he reasoned, with a bit of ice in your drink, you would be at break even. With less than five grams, less than a quarter ounce, you should be able to drink cocktails all day long and lose weight like crazy. The logic is ironclad, but alas, in practice, it isn’t so. Logic, thus fails us.

Except, of course, that dietary calories are actually measured in kilocalories. So in point of fact, if your drink has 350 calories, that gin and tonic is actually 350,000 calories. So to balance that out, you would need to eat three kilograms of ice (80 calories per gram to melt it and 37 calories per gram to heat it up to body temperature comes out to 117 calories per gram, divided into 350,000 calories yields 2991 grams). So the not-so-intelligent but nevertheless diligent fact-checkers realize that they’re going to need a hell of an ice maker to keep up with their weight loss program.

But this is not meant as a weight-loss guide. I just want to point out two things.

Logic does not betray us. We betray logic by feeding in poor assumptions and by failing to reason logically from otherwise good (or bad, in the case of the Nazis) assumptions.

It is the belief that logic can betray us that creates the opening for illogic. If you believe that reason can fail, that gut reactions trump logical arguments, that common sense is a better guide, you create the conditions where you don’t ask the right questions, where you let bad answers stand and, ultimately, you make bad decisions.

If your gut reaction tells you something seems wrong, then you need to question it and put it to the test of reason. But here’s the thing: if your gut reaction tells you that something is right, then you need to question it and put it to the test of reason. That’s what separates research from reverie, scholars from pundits, facts from opinion, staring from blinking and, while we’re at it, creationism from science.

About Raised by Turtles

There’s not much to say. This site is maintained (to put it charitably!) by Tom Lambert. Sometimes I have things to write about. Some of those I actually do write about. A proportion of those might even be worth writing about. If you don't agree, nobody shackled you to a keyboard. A more interesting blog is just one click away.

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